Milestones: 1969–1976

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Détente and Arms Control, 1969–1979

Between the late 1960s and the late 1970s, there was a thawing of the ongoing
Cold War between the United States and the Soviet Union. This détente took
several forms, including increased discussion on arms control. Although the
decade began with vast improvements in bilateral relations, by the end of the
decade events had brought the two superpowers back to the brink of
confrontation.

Conference on Security and Co-operation in Europe, 1975. (Deutsches
Bundesarchiv)

Two decades after the Second World War, Soviet-American tension had become a way
of life. Fears of nuclear conflict between the two superpowers peaked in 1962 in
the wake of the Cuban
Missile Crisis, paving the way for some of the earliest agreements on
nuclear arms control, including the Limited Test Ban Treaty in
1963. Although these agreements acted as important precedents, the U.S.
escalation of the war in Vietnam increased tensions again and served to derail
any efforts in the mid-1960s to pursue further arms agreements. By the late
1960s, however, both countries had several concrete reasons for resuming arms
talks. The ongoing nuclear arms race was incredibly expensive, and both nations
faced domestic economic difficulties as a result of the diversion of resources
to military research. The emergence of the Sino-Soviet split also made the idea
of generally improving relations with the United States more appealing to the
USSR. The United States faced an increasingly difficult war in Vietnam, and
improved relations with the Soviet Union were thought to be helpful in limiting
future conflicts. With both sides willing to explore accommodation, the early
1970s saw a general warming of relations that was conducive to progress in arms
control talks.

In practical terms, détente led to formal agreements on arms control and the
security of Europe. A clear sign that a détente was emerging was found in the
signing of the Nuclear Nonproliferation
Treaty in 1968. Then, in 1972, the first round of Strategic Arms Limitations Talks
yielded the Antiballistic Missile Treaty along with an interim agreement setting
caps on the number of intercontinental ballistic missiles each side could
develop. At mid-decade, in 1975, the Conference on Security and Cooperation in
Europe emerged from two years of intense negotiations to sign the Helsinki Final Act, which
recognized political borders, established military confidence building measures,
created opportunities for trade and cultural exchange, and promoted human
rights. By the end of the decade, however, cracks had begun to form in the
precarious U.S.-Soviet relationship. The leadership of the two countries signed
a second SALT agreement but did not ratify it, although both nations voluntarily
adhered to the provisions for reduced limits on strategic weapons for years
thereafter.

The breakdown of détente in the late 1970s stalled progress on arms control.
Ultimately, the United States and the Soviet Union had different visions of what
détente meant and what its pursuit would entail. Overblown expectations that the
warming of relations in the era of détente would translate into an end to the
Cold War also created public dissatisfaction with the increasing manifestations
of continued competition and the interventions in the Third World. By the time
the Soviet Union invaded Afghanistan in 1979, the spirit of cooperation had been
replaced with renewed competition and formal implementation of the SALT II
agreement stalled. Arms control talks ceased in the early 1980s and only
restarted when Mikhail Gorbachev came to power in the
Soviet Union.